1. Field of the Invention
The invention relates to interface appliances for delivering a breathable substance to a subject while obtaining samples of gas at or near the airway of the subject for monitoring.
2. Description of the Related Art
Subject interface appliances configured to support breathable substances for therapeutic purposes are known. Conventional use of these appliances includes using a primary interface appliance configured to deliver the breathable substance and a separate secondary interface appliance configured to obtain gas samples from gas exhaled from the airway of the subject. These primary and secondary interface appliances are generally formed as separate interface appliances that are used together in some therapeutic settings. Installing both the primary and secondary interface appliance on the face of a subject may be difficult due to mechanical interference between the two interface appliances (and/or the mechanisms that hold these appliances in place), and/or due to isolation of the secondary interface appliance from a user by the primary interface appliance.